Acoustic Neuroma

Acoustic Neuroma Program

acoustic_nhomeAcoustic neuroma is a non-cancerous tumor located at the base of the brain, originating from one of the balance nerves within the internal auditory canal. As it grows, it presses against several nerves and creates problems in hearing, balance, facial movement and facial sensation. Left unchecked, it may press on the brainstem and become life threatening.

Overview

The cause of acoustic neuromas in most patients is unknown. According to the Acoustic Neuroma Association, estimates of the incidence of symptomatic acoustic neuroma vary from one in every 200,000 people to one in every 3,500 people. Other studies indicate a more frequent incidence, perhaps as high as 1.5% of the population. Most acoustic neuromas are diagnosed on patients between the ages of 30 and 60.

A multidisciplinary team of specialists, including neurosurgeons, otolaryngologists, neurologists, radiation oncologists, neuro-ophthalmologists and rehabilitation specialists provide diagnosis and treatment of acoustic neuromas. For most patients, partial or complete eradication of the tumor is necessary. Surgical options include microsurgery, stereotactic radiation therapy and fractionated radiosurgery.

Surgical Options

Surgical Options

The most common option involves microsurgery, in which the tumor is surgically removed. The tumor is accessed through one of three approaches (translabyrinthine, retrosigmoid [suboccipital], or middle cranial fossa). The selection of the approach is based on tumor size and location, as well as the amount of hearing that the patient has before surgery.

Microsurgery is performed using high-powered microscopes and delicate surgical instruments. The surgery usually lasts between 4 to 12 hours and involves an experienced neurosurgeon and otolaryngologist (neuro-otologist) team who perform the surgery together. Hospital stays range from four to seven days, with an average of four to six weeks recovery time.

The second surgical option is radiosurgery, or stereotactic radiation therapy, a non-invasive procedure that uses high-dose-rate radiation to destroy the tumor. Unlike conventional radiation therapy, in which multiple doses of radiation are delivered over several weeks of treatment, radiosurgery involves only a single dose-delivered to the precise location of the tumor.

The third option is fractionated radiosurgery, in which multiple fractions of radiation-delivered at varying angles-are focused on the tumor site. The Froedtert & The Medical College of Wisconsin Neurosciences Center is the first in Wisconsin to have advanced Gamma Knife technology available for this use. The Gamma Knife unit is the world standard for superselective irradiation of tumors and uses advanced imaging technology to identify the exact size, shape and location of the tumor. Once the tumor has been pinpointed, the Gamma Knife directs 201 converging beams of radiation on the site, sparing adjacent tissue of clinically significant radiation.

An important characteristic of the Acoustic Neuroma Program is that a surgical team approach is used not only for the microsurgical removal of tumors but also for the stereotactic radiosurgical treatment of tumors.

This collaborative approach utilizing the expertise of a neuro-otologist and neurosurgeon team is designed to enhance clinical outcomes.

In addition to the Gamma Knife, the surgical team has access to a LINAC-based radiosurgery system. In this system, a relocatable, mask-based, stereotactic head ring is used to direct the fractionated radiation beams. The system uses the same stereotactic localizing technique as used for Gamma Knife treatments, thereby assuring that the radiation dose tightly conforms to the shape of the targeted tumor. The fractionated LINAC-based system is typically used for tumors that are too large to be treated using Gamma Knife technology.

All three surgical options are available within the Froedtert & The Medical College of Wisconsin Neurosciences Center. Medical and surgical specialists are available to consult with patients and help them choose the most appropriate treatment option.

Specialists

Neurosurgery

Otolaryngology and Communication Sciences

David R. Friedland, MD, PhD
Medical College of Wisconsin Neurotologist
Director, Acoustic Neuroma Program

Radiation Oncology

Michael T. Gillin, PhD
Medical College of Wisconsin Biophysicist

Christopher J. Schultz, MD
Medical College of Wisconsin Radiation Oncologist

Facial Plastic and Reconstructive Surgery

Hani S. Matloub, MD
Medical College of Wisconsin Plastic and Reconstructive Surgeon

John S. Rhee, MD
Medical College of Wisconsin Plastic and Reconstructive Surgeon

Ophthalmology

Gerald J. Harris, MD
Medical College of Wisconsin Ophthalmologist

Steven B. Koenig, MD
Medical College of Wisconsin Corneal Surgeon

Medical Genetics

William J. Rhead, MD, PhD
Medical College of Wisconsin Geneticist